¹ See, e.g., Anthony Dworkin, Europe's New Counter-terror Wars, at 2 (European Council on Foreign Relations Policy Brief Oct. 2016) (reviewing the counterterrorism policies of several European states and concluding that “there has been a notable and largely unremarked convergence between European and US approaches to military action against terrorists, after many years when they differed widely”).

² See Hakimi, Monica, A Functional Approach to Targeting and Detention , 110 Mich. L. Rev. 1365, 1392–95 (2012)Google Scholar; Hakimi, Monica, Taking Stock of the Law on Targeting, Part I , EJIL Talk! (Dec. 12, 2016)Google Scholar, at http://www.ejiltalk.org/taking-stock-of-the-law-on-targeting-part-i.

³ Isayeva v. Russia, App. No. 57950/00, 41 Eur. H.R. Rep. 791, 833 (2005).

⁴ Khatsiyeva v. Russia, App. No. 5108/02, paras. 134–39 (Eur. Ct. H.R. 2008).

⁵ Finogenov v. Russia, App. No. 18299, para. 211 (Eur. Ct. H.R. 2011) (“[T]he Court may occasionally depart from that rigorous standard of ‘absolute necessity’ … [if] its application may be simply impossible where … the authorities had to act under tremendous time pressure and where their control of the situation was minimal.”).

⁶ Al-Skeini v. United Kingdom, App. No. 55721/07, para. 164 (Eur. Ct. H.R. 2011).

⁷ Id., para. 165.

⁸ Id., para. 164.

⁹ Presidential Policy Guidance: Procedures for Approving Direct Action Against Terrorist Targets Located Outside the United States and Areas of Active Hostilities (May 22, 2013), available at https://www.justice.gov/oip/foia-library/procedures_for_approving_direct_action_against_terrorist_targets/download.

¹⁰ E.g., Hassan v. United Kingdom, App. 29750/09, paras. 96–111 (Eur. Ct. H.R. 2014); Case of the “Mapiripán Massacre” v. Colombia, Merits, Reparations, and Costs, Judgment, 2005 Inter-Am. Ct. H.R. (ser. C) No. 134, paras. 114–15 (Sept. 15).

¹¹ E.g., Nils Melzer, ICRC, Interpretive Guidance on the Notion of Direct Participation in Hostilities Under International Humanitarian Law 77–82 (2009).

¹² E.g., infra notes 24–25 and accompanying text (discussing Israeli and U.K. judicial decisions); Hamdi v. Rumsfeld, 542 U.S. 507 (2004) (J. O'Connor, plurality) (using a mix of U.S. domestic law and IHL principles to uphold, and then to impose procedural limits on, the government's authority to detain people administratively).

¹³ See, e.g., Ryan Goodman & Derek Jinks, Socializing States: Promoting Human Rights Through International Law 111–12 (2013) (“A common view is that human rights treaties should aspire to greater levels of precision to foster compliance and enforcement.”); MacLaren, Malcolm & Schwendimann, Felix, An Exercise in the Development of International Law: The New ICRC Study on Customary International Humanitarian Law , 6 German L.J. 1217, 1240 (2005)Google Scholar (“[I]t is incontestable on general legal and practical considerations that such attempts to clarify existing rules can facilitate the rules' effectiveness and improvement.”).

¹⁴ E.g., Chayes, Abram & Chayes, Antonia Handler, The New Sovereignty: Compliance with International Regulatory Agreements 10 (1995)Google Scholar (“[A]mbiguity and indeterminacy of treaty language lie at the root of much of the behavior that might seem to violate treaty requirements.”); Franck, Thomas M., Legitimacy in the International System , 82 AJIL 705, 714 (1988)CrossRefGoogle Scholar (“Indeterminate normative standards not only make it harder to know what conformity is expected, but also make it easier to justify noncompliance.”); Guzman, Andrew T., A Compliance-Based Theory of International Law , 90 Calif. L. Rev. 1823, 1863 (2002)CrossRefGoogle Scholar (“As the uncertainty of an obligation increases, the reputational cost from the violation decreases.”).

¹⁵ E.g., Brunnée, Jutta & Toope, Stephen J., Legitimacy and Legality in International Law 351 (2010)CrossRefGoogle Scholar (explaining that the criteria of law include clarity in content and consistency in application); Abbott, Kenneth W., Keohane, Robert O., Moravcskik, Andrew, Slaughter, Anne-Marie & Snidal, Duncan, The Concept of Legalization , 54 Int'l Org. 401, 414 (2000)CrossRefGoogle Scholar (“[P]recision and elaboration are especially significant hallmarks of legalization at the international level.”).

¹⁶ We can analogize here to the distinction that some philosophers draw between “practice-independent” and “practice-dependent” theories of human rights. (I am indebted to Christopher McCrudden for bringing my attention to this distinction.) In practice-independent theories, the justification for and content of human rights are not constrained by the historically contingent and politically compromised practices that we happen to live with; human rights principles are derived through other means, like morality or intuition, and then used to assess or try to reform that practice. Carrying the analogy forward, much of the work on the relationship between IHL and IHRL is practice-independent in the sense that it begins with a jurisprudential vision—an idea of what law is or how law functions—and then uses that vision to evaluate the practice. By contrast, practice-dependent theories define and justify human rights in terms of the particular institutional or cultural contexts in which they arise. Such theories ask not whether a given practice conforms to an externally derived ideal but what functions it does or might serve in the real world. The practice-dependent approach is like the one that I am advancing. For excellent overviews of this distinction in the philosophical literature, see Christopher McCrudden, Human Rights: Law, Politics, and Philosophy (draft manuscript on file with author); and Sangiovanni, Andrea, Justice and the Priority of Politics to Morality , 16 J. Pol. Phil. 137 (2008)Google Scholar.

¹⁷ E.g., Dehn at 317 (“Disputes regarding the applicable legal framework stem largely from [a set of normative] disagreements… .”); Luban at 49 (“[T]he legalisms are pretty clearly a stand-in for a broader debate about the very nature of war and peace and the laws that regulate them, and that debate is not technical at all.”); Milanović at 78, 81(describing a debate that is “waged between two camps” of international lawyers, who exploit the “unbearable” complexity in the law to advance their preferred policies); Ohlin at 119 (“It is no surprise, then, that the choice of framework question is contentious and bitter.”).

¹⁸ Jean-Marie Henckaerts & Louise Doswald-Beck, Int'l Comm. Red Cross, 1 Customary International Humanitarian Law, at xxxv (2005) (“State practice … has led to the creation of rules parallel to those in Additional Protocol I, but applicable as customary international law to non-international armed conflicts.”).

¹⁹ See Sivakumaran, Sandesh, The Law of Non-international Armed Conflict 56–57, 61 (2012)Google Scholar.

²⁰ For a discussion of and critique of this method, see Hakimi, A Functional Approach to Targeting and Detention, supra note 2.

²¹ Melzer, supra note 11.

²² See, e.g., Parks, W. Hays, Part IX of the ICRC “Direct Participation in Hostilities” Study: No Mandate, No Expertise, and Legally Incorrect , 42 N.Y.U. J. Int'l L. & Pol. 769 (2010)Google Scholar; Schmitt, Michael N., The Interpretive Guidance on the Notion of Direct Participation in Hostilities: A Critical Analysis , 1 Harv. Nat'l Security J. 5 (2010)Google Scholar; Watkin, Kenneth, Opportunity Lost: Organized Armed Groups and the ICRC “Direct Participation in Hostilities” Interpretive Guidance , 42 N.Y.U. J. Int'l L. & Pol. 641 (2010)Google Scholar.

²³ E.g., Isayeva v. Russia, supra note 3; Al-Skeini v. United Kingdom, supra note 6.

²⁴ HCJ 769/02 Pub. Comm. Against Torture in Isr. v. Israel, 2006(2) Isr. Rep. 459, 490–95 [2005] (Isr.).

²⁵ Al-Waheed v. Ministry of Defense & Serdar Mohammed v. Ministry of Defense, [2017] UKSC 2, Jan. 17, paras. 12–14; see also id., paras. 235(ii), 256–57, 271–76 (dissenting opinion of Lord Reed); Serdar Mohammed v. Secretary of State for Defense, [2014] EWCA Civ. 843, paras. 9(ii)(c), 164–253 (U.K. Court of Appeal).

²⁶ See McCrudden, Christopher M., Is the Principal Function of International Human Rights Law to Address the Pathologies of International Law? A Comment on Patrick Macklem's The Sovereignty of Human Rights, 67 Toronto L.J. 623, 628 (2017)Google Scholar (“Any legal decision about a contested area of human rights is often quite provisional and subject to varying degrees of continuing legal debate and challenge.”); cf. Reisman, W. Michael, The Democratization of Contemporary International Law-Making Processes and the Differentiation of Their Application , in Developments of International Law in Treaty Making 15, 28–29 (Rüdiger Wolfrum & Volker Röben eds., 2005)Google Scholar (“Because the question of whether international law will be effective in a particular dispute will increasingly depend upon the arena or forum in which the dispute is heard, scholarly and practitioner statements of what the law is … will increasingly have to be qualified by reference to where a potential dispute in the future may initially be characterized in terms of law and where those characterizations will thereafter be put to political use.”).

²⁷ The doctrine on sources reinforces this vision because it defines international law in consensual terms. See, e.g., Military and Paramilitary Activities in and Against Nicaragua (Nicar. v. U.S.), Judgment, 1986 ICJ Rep. 14, para. 269 (June 27) (“[I]n international law there are no rules, other than such rules as may be accepted by the State concerned… .”).

²⁸ E.g., Orakhelashvili, Alexander, The Interpretation of Acts and Rules in Public International Law 29 (2008)CrossRefGoogle Scholar (“[P]olitical considerations are inherently subjective and can be subjectively manipulated, unlike accepted rules of law.”); Shaw, Malcolm N., International Law 12 (6th ed. 2008)CrossRefGoogle Scholar (“Power politics stresses competition, conflict and supremacy … [while] law aims for harmony and the regulation of disputes.”).

²⁹ Koskenniemi, Martti, From Apology to Utopia: The Structure of International Legal Argument 565, 567–68 (2d ed. 2006)CrossRefGoogle Scholar (describing international law as a common grammar that does not necessarily reflect the participants' shared substantive commitments but instead structures an argumentative practice); Venzke, Ingo, Semantic Authority, Legal Change and the Dynamics of International Law , 12 No Foundations 1, 2, 12 (2015)Google Scholar (arguing that “[t]he law provides the battleground for competing claims,” such that “different actors with varying degrees of semantic authority struggle” over its meaning).

³⁰ Kutz, Christopher L., Just Disagreement: Indeterminacy and Rationality in the Rule of Law , 103 Yale L.J. 997, 1028 (1993)Google Scholar.

³¹ de Búrca, Gráinne, Human Rights Experimentalism , 111 AJIL 277 (2017)CrossRefGoogle Scholar.

³² Id. at 280.

³³ For an argument to this effect, see Jack Goldsmith, Power and Constraint: The Accountable Presidency After 9/11 (2012).

³⁴ Jaffer tries to paint a different picture. He describes a “policy of obfuscation” and “stonewalling” by an executive branch intent on keeping “[b]asic information … secret even from the courts and Congress” (p. 25). However, Jaffer also recognizes that “[c]ontroversy over drone strikes compelled the Obama administration to discuss the campaign publicly in more detail” (p. 20) and that “the gap between what the government said was secret and what was actually secret became increasingly difficult for the government to manage and increasingly difficult for the courts to ignore” (p. 31). Indeed, the collection of documents that comprise the bulk of the book show that, largely because of efforts like Jaffer's, much about U.S. lethal operations is now publicly available.

³⁵ Hakimi, Monica, The Work of International Law , 58 Harv. Int'l L.J. 1 (2017)Google Scholar; Hakimi, Monica, Constructing an International Community , 111 AJIL 317 (2017)CrossRefGoogle Scholar; see also McCrudden, supra note 26, at 14 (“[T]he lack of resolution of the contradictions in the international adjudication of human rights law disputes, for example, is not to be regarded as a failure but, rather, as an essential element of the practice of human rights. The practice … becomes the site of provisional and (politically) temporary accommodation that helps us to live together, despite the basic conflicts that are brought to court.”).

³⁶ See Tsutsui, Kiyoteru, Human Rights and Minority Activism in Japan: Transformation of Movement Actorhood and Local-Global Feedback Loop , 122 Am. J. Sociology 1050 (2017)CrossRefGoogle Scholar.

³⁷ See, e.g., Johan Karlsson Schaffer, The Point of the Practice of Human Rights: International Concern or Domestic Empowerment?, available at https://papers.ssrn.com/sol3/papers.cfm?abstract_id=2564514 (manuscript at 14) (arguing that human rights are “power-mediators that provide relatively weak social agents with normative resources for challenging political authority”).